The proposed program of research will focus on essential memory skills involved in disregarding irrelevant information in memory. These skills are important since the failure to ignore irrelevant information in memory may interfere with the processing of relevant information, and learning efficiency will decrease. Both mentally retarded and normal children will be studied using a memory task in which, periodically, the child is instructed to forget information which he/she was previously instructed to remember. The research projects will focus on three separate but related issues: (1) age changes in performance, task conceptualization, comprehension processes, and using memory for a purpose on tasks requiring that irrelevant information be disregarded; (2) the relationship of metamemory to task performance when irrelevant information must be disregarded, and (3) the importance of disregarding irrelevant information on everyday learning tasks such as following verbal instructions and recalling the gist of discourse.